This is incorrect. The courts already ruled on a similar situation: sampling.
"In the case of Bridgeport Music, Inc. v. Dimension Films [2005], the US federal appeals court established that recording artists must clear every musical sample in their work, even minor, unrecognised “snippets” of music. The court rejected the notion that using unidentifiable musical snippets was legal, making clear the need for artists to obtain licences for any sampled content.
This decision emerged from a case involving the N.W.A. song 100 Miles and Runnin’, which sampled a guitar riff from George Clinton and Funkadelic’s Get Off Your Ass and Jam. The court’s stance underscores the imperative to secure licences and dismisses the idea that such requirements stifle creativity."
it's all right here: https://www.scottishlegal.com/articles/opinion-music-sampling-and-copyright-disputes#:~:text=The court rejected the notion,a case involving the N.W.A.
no one is saying that it's going to stop. If you want to train on someone's content, you must get a license. It's that simple.